Signal conversion device



FIG. 1 is a front elevation view of a signal conversion device showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a left side view elevation thereof; and,

FIG. 7 is a top, perspective view thereof. 

CLAIM The ornamental design for a signal conversion device, as shown and described. 